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It's time to reconsider our irrational (actually inherited) opposition to "security through obscurity" [ * ]. In times when big brother knows you're using AES

It's time to reconsider our irrational (actually inherited) opposition to "security through obscurity" [ * ]. In times when big brother knows you're using AES and forcibly asks you for the keys, it makes sense to not advertise your encryption scheme at all. Steganography. [ * ] It actually makes more sense to enlarge the search space of an attacker by not providing him the fixed form of a known encryption algorithm/scheme.

mindslight 11y ago
The formal name for the concept is Kerckhoffs's principle. And no, it is not time to reconsider it. It has more to do with defining what the "key" is, and is quite compatible with steganography. If your method is simply "cipher data", it can never have steganographic properties.. If instead it's "two redundant-looking blobs, one random and one AES", then you've got a leg to stand on.
- crististm 11y ago
  You are free to stand by your principles. I'm arguing that "security through obscurity" is not equivalent with the "Kerckhoffs's principle" but with adding more obfuscation layers (on which steganography may be one of them) on top of default schemes. People who know better don't advertise their internal network topology. Nor do they show off with their encryption schemes (they might use known schemes but they won't tell you they do it).
  - mindslight 11y ago
    How those additional layers are defined is quite important as to their effectiveness - do they hold up to scrutiny, or are they merely good enough to trick their designer? Lumping effective crypto along with feel-good ad-hoc schemes into one big category of "obfuscation" is a disservice to analysis. I'll repeat - Kerckhoffs's principle is more about analysis than design. If you insist on eschewing it, what you're actually doing is making it so the "key" of your system includes the design of the system itself. And while it intuitively seems "more key" should make the system more secure, the net effect is the opposite as that poorly-specified "key" merely functions as a difficult-to-analyze crutch. Gödel basically guarantees that anybody can make a cryptosystem so secure they themselves cannot break it. Don't be that guy.
serge2k 11y ago
Security through obscurity is not steganography.

mindslight 11y ago

The formal name for the concept is Kerckhoffs's principle. And no, it is not time to reconsider it. It has more to do with defining what the "key" is, and is quite compatible with steganography. If your method is simply "cipher data", it can never have steganographic properties.. If instead it's "two redundant-looking blobs, one random and one AES", then you've got a leg to stand on.

crististm 11y ago
You are free to stand by your principles. I'm arguing that "security through obscurity" is not equivalent with the "Kerckhoffs's principle" but with adding more obfuscation layers (on which steganography may be one of them) on top of default schemes. People who know better don't advertise their internal network topology. Nor do they show off with their encryption schemes (they might use known schemes but they won't tell you they do it).
- mindslight 11y ago
  How those additional layers are defined is quite important as to their effectiveness - do they hold up to scrutiny, or are they merely good enough to trick their designer? Lumping effective crypto along with feel-good ad-hoc schemes into one big category of "obfuscation" is a disservice to analysis. I'll repeat - Kerckhoffs's principle is more about analysis than design. If you insist on eschewing it, what you're actually doing is making it so the "key" of your system includes the design of the system itself. And while it intuitively seems "more key" should make the system more secure, the net effect is the opposite as that poorly-specified "key" merely functions as a difficult-to-analyze crutch. Gödel basically guarantees that anybody can make a cryptosystem so secure they themselves cannot break it. Don't be that guy.

serge2k 11y ago

Security through obscurity is not steganography.